A few questions concerning Tweed

I haven't had any tweed before, but I think it's about time I start wearing it, so I have a few questions.

Firstly, how is wearing the different pieces of a tweed suit separately viewed? A business suit with pinstripes for example I'd never wear as anything but the complete suit, but plenty of people seem to wear tweed jackets that are a part of a suit as sportscoats. Is this one of those things people do but shouldn't, or is it perfectly acceptable? How about the suit-trousers, are they equally acceptable to wear with just a shirt and a cardigan (or whatever)? I'm not talking just a garment made from the tweed material, but a classic green-ish tweed suit with some form of windowpane pattern.

Secondly, is it acceptable (these days) to wear tweed in the city? Not talking about dressing up in a 3-piece tweedsuit with tattersal shirt and a woven wool tie, but just using the jacket of a tweedsuit together with perhaps moleskin or cord trousers. The city most relevant to me is london by the way. And does this vary with the different colours and/or patterns?

Thirdly, does the informality of the suit need to match the informality of the shirt? I'm not a big fan of tattersal, but I do love white poplin and herringbone shirts, are these acceptable to wear with tweed, or is there too much of a formality mismatch, like jeans with black oxfords? Also, does this depend on whether you're wearing it as a sportscoat or as a full 3-piece suit?

And lastly, are anyone familiar with the offerings of Cordings of Piccadilly? Can anyone who is tell me about their estimation of the cordings tweed garments? I've noticed that the styling seems quite traditional, and they have working buttonholes on the sleeves, but if anyone has anything to add to that, I'd be grateful. Material quality, construction (full canvas?) , fit and styling too for that matter? Any input is appreciated.

Wearing the pieces of a tweed suit as separates is fine, because they're not obviously parts of a suit. The problem with doing that with worsteds or pinstripes is that those fabrics are pretty much never used outside of suits, and it's obvious what you're doing. Tweed jackets/ trousers/wasitcoats are all routinely worn as separates. Texture and pattern allows for more flexibility in doing something like that. There's no actual difference in the garments from what you would buy as separate tweed pieces, which is how most tweed is worn these days.

The formality of the shirt does not have to match. Wear a nice shirt and a smooth silk tie to dress tweed up, wear a rough oxford with a knitted or no tie for a much more casual look- which, incidentally, works great with a nicely beat up and worn in tweed jacket. The nice shirt and tie would probably not work all that well for the beat up jacket, however. But by the time your first is beat up, you may not care since the jacket is too comfy, or you may have more in the stable. Starting down the road of tweed seems to have both those effects on people- wearing a broken in tweed jacket is like wearing a soft wool blanket.

If you're wearing the jacket independently, cords or flannel trousers are fairly natural accompaniments. Jeans are popular for casual wear- the utilitarian heritage and the texture of both fabrics make them a happy pairing. To wear the trousers, a sportcoat with decent weight or just about any sweater manly enough to stand up to them- something decently warm or something with a fair amount of texture. The vest could probably go under many two piece suits on a cool day or to bring the formality down a notch.

As for propriety in London for business, my guess would be that it would be perfectly fine anywhere where a sportcoat and trousers would be acceptable. I don't live there and haven't been there since I was in middle school (not sure where that falls in the brit system - 6th-8th grade) though, so I can't speak authoritatively on that point.

That's awesome, thanks for the answers and thanks for the link, some great stuff there. I'm relieved to see that the selection of shirts that can be worn with tweed is so wide, and bengal-stripes look great with it apparently, not sure I'd have thought of that on my own right away.

A few more questions though. Concerning tweed suits, should they be 3-piece, or is it fine to wear them as 2 piece? Most pictures I've seen of "tweed done right" in the traditional way has been 3-piece suits, so should I get a waistcoat as well to wear it the way it should be worn?

When you talk of wearing the vest with 2-pieces suits, are you talking about the tweed waistcoat as an addition to a different 2-piece business-suit? Or a different tweed suit, like jacket and trousers in a green tweed with a sand-coloured tweed waistcoat or something like that?

I was thinking of wearing grenadine ties with tweed as it has a nice rough texture and slightly casual nature, while at the same time is very elegant, but how dressy can you get with ties together with tweed? Silk woven critter ties with hunting motifs is a natural thing, but how about satin silk ties, or more formal macclesfield ties?

Also, how long does it take for tweed to get "beat up"? Tweed is well known to be hard wearing, so I don't expect to find holes in it any time soon, but does the open-ness of the weave make it loose shape sooner than say a business-suit? Compared to a business-suit, how long will the tweed remain in "good" condition (ie remain in proper shape and presentable) before it becomes as you say beat up and feels like a blanket but is less suitable with nice shirts and ties?

Lastly, can anyone comment on the quality of the materials and construction of the offerings by Cordings of Picadilly? Has anyone had tweed suits/jackets from Cordings? Does anyone know if it's fused at all or traditional full canvas?

If by City you're referring to financial/law firms in the square mile then aside from "casual friday" (which my work doesn't operate, and don't know of any of the BB banks that do) tweed isn't acceptable as a suit or otherwise unfortunately.

Regard a new tweed jacket like a pair of fine shoes, they need 'breaking in' , especially if it is a substantial cloth.Don't expect it to lie just as you would want straight out of the box. It will 'mould' to your shape.
Softer but still 'real' tweeds like the Saxony's take less time. For the heaviest cloths, make provision in your will to pass them on as they'll mostly outlive us all:D